This invention relates to a visible light activated polymerization process for the production of high molecular weight polymers with the aid of copper ions.
Many processes are known in the prior art for the preparation of polymers by photopolymerization, such as those disclosed in U.S. Pat. Nos. 2,850,445; 2,880,152 and 2,880,153. These processes, however, suffer from a variety of disadvantages, such as high capital cost, low monomer conversion, high energy requirements, low polymer molecular weight formation and numerous other problems. Copending applications, U.S. Ser. No. 335,795, filed Dec. 30, 1981, and U.S. Ser. No. 155,261, filed June 2, 1980, are directed to processes using visible light activated polymerization. The improvement disclosed herein is a useful improvement of both of the described processes and they are hereby incorporated into this disclosure by reference.
The advantage of the present invention is that by the introduction of copper ions into the photopolymerization process, polymerization occurs at much lower concentration of reducing agent and photoreducible dye, thus allowing for a significant increase in the molecular weight of the product polymer.